Process and apparatus for treating a continuous length of synthetic textile fabric for the purpose of making the material softer, less glossy and more voluminous



Dec. 17, 1968 R; NORDMANN 3,416,881

PROCESS AND APPARATUS FOR TREATING A CONTINUOUS LENGTH OF SYNTHETIC TEXTILE FABRIC FOR TH PURPOSE OF MAKING THE MATERIAL SOFTER, LESS GLOSSY AND MORE VOLUMINOUS Filed Oct. 6, 1965 2 Sheets-Sheet 1 A; 2a 1 96 /9 H V II II ll Km, INVENTOR BY m E M Q ATTORNEYS Dec. 17, 1968 R. NORDMANN 3,416,881

PROCESS AND APPARATUS FOR TREATING A CONTINUOUS LENGTH OF SYNTHETIC TEXTILE FABRIC FOR THE PURPOSE OF MAKING THE MATERIAL SOFTER, LESS GLOSSY AND MORE VOLUMINOUS Filed Oct. 6, 1965 2 Sheets-Sheet 2 22 32 2/ 34 R d? PM INVENTOR ATTORNEY 5 United States Patent 3 416 881 PROCESS AND APPARATUS FOR TREATING A CONTINUOUS LENGTH OF SYNTHETIC TEX- TILE FABRIC FOR THE PURPOSE OF MAKING THE MATERIAL SOFTER, LESS GLOSSY AND MORE VOLUMINOUS Ren Nordmann, Montceau-les-Mines, France, assignor to Ultrasona A.G., Zurich, Switzerland Filed Oct. 6, 1965, Ser. No. 493,509 Claims priority, application Denmark, Oct. 12, 1964, 5,029/64 8 Claims. (Cl. 8130.1)

This invention relates to a process for treating a continuous length of synthetic textile fabric for the purpose of making the material softer, less glossy and more voluminous.

The fabric to be treated may be knitted or woven fabric, or a fabric made by any other of the methods utilized in the textile industry for the manufacture of fabrics.

Fabrics made from synthetic yarn material such as polyamides, acrylonitriles, acetates and triacetates, polyesters and polyvinyl chlorides, while having excellent properties in many respects, suffer from the drawbacks, as compared with fabrics from natural yarn material of vegetable or animal origin, that they have a hard touch and a rather glossy appearance. Besides, they have poor heat insulating properties and will only absorb or adsorb very small quantities of moisture.

In order to remove these drawbacks, a process has been proposed according to which the textile goods are first subjected to treatment in a strongly attacking shrinking bath, while at the same time being subjected to ultrasonic waves, and are immediately thereafter washed with a Washing liquid that may contain a neutralizing agent for the shrinking liquid.

As a shrinking liquid a phenol solution of 38% has up to now primarily been used for the treatment of polyamides, but many others may come into consideration, depending on the type of synthetic textile material, eg for polyamides: phenol derivatives, concentrated acids such as hydrochloric acid or concentrated formic acid; for acrylonitriles: alkali solutions, concentrated mineral acids, dimethyl formamide; for acetates and triacetates: acetone, formic acid, acetic acid or phenols; for polyesters: strong alkali solutions, sulfuric acid, or phenol; for polyvinyl chlorides: acetone, trichloroethylene, nitrobenzene, chloroform or phenol.

As a result of this known process, the filaments or fibres are spread apart between the intersecting or linking points of the textile pattern, whereby a great number of small cavities are formed between the individual filaments or fibres, which cavities will give the thread as a whole somewhat more flutfy contours, whereby the fabric becomes more voluminous and less glossy, and will also contribute towards increasing the heat insulating and moisture adsorbing or absorbing properties.

However, very great difficulties have been encountered in adapting this method to commercial practice On an economically sound basis. The principal source of these difliculties is the fact that, in order to obtain useful results, it has been found necessary to operate at very short and well-defined times of treatment, viz, only a fraction of one minute in the shrinking bath. If the time of treatment is increased and the concentration of the shrinking agent is made correspondingly lower, it is found that just a uniform shrinking, but no spreading of the filaments or fibres will take place.

It has been attempted to obtain the desired short and well-defined time of treatment by conveying the goods through the bath between two synchronously travelling belt conveyors. While it is possible in this manner to obtain a good control of the time of treatment, it has been found that the goods will become nonuniform and stained in part, which is ascribable to the fact that it is not possible in the manner described to obtain a uniform penetration of the liquid of the bath into all surface portions of the textile article, and that there will be considerable danger of the formation of inner tensions in the textile fabric and warping of the textile pattern, because the fabric does not have full freedom of movement in all directions and is therefore not free to yield to the shrinking influences to which it is subjected.

In order to avoid these drawbacks, a method has been proposed for the treatment of textile goods of limited length, according to which the textile goods are conveyed in a continuous movement through the bath from one end to the other of this in a freely floating condition.

However, this method is not applicable to the treatment of fabrics of considerable length, because the portion of the fabric at any time present in the shrinking bath is in continuous connection with the preceding and subsequent portions of the fabric and therefore cannot float absolutely freely in the shrinking bath. Moreover, continuous lengths of textile fabric have a. so great area of fabric present in the shrinking bath at a time that folds or other irregularities would inevitably be formed if the fabrics were entirely left to themselves during their travel through the shrinking bath.

It is the object of the invention to pass a continuous length of textile fabric through a shrinking bath in such a manner that it is caused to move in a flatly spread state in a well-defined path of movement through the shrinking bath but is still kept practically free of tensions and has full freedom of contracting under the influence of I the shrinking effect to which it is subjected.

According to the invention, the textile fabric is passed through the shrinking bath in a path of movement extending under a perforated belt conveyer immersed in the bath, the speeds of supply and removal of the textile fabric to and from the shrinking bath and the speed of movement of the belt conveyor being so mutually adjusted that practically no tensile stresses occur in the textile fabric, and the latter is caused to follow a path of movement extending substantially along the underside of the belt conveyor.

Hereby the advantage is obtained that the textile fabric will engage the underside of the perforated belt conveyor over the major part of its travel through the shrinking bath at an engagement pressure which is so small as not to prevent the textile fabric from freely following the shrinking effect to which it is subjected, while on the other hand the engagement pressure is sufficiently great to keep the textile fabric flatly spread so that the formation of folds and other irregularities is avoided. Moreover, when the belt conveyor is made sufficiently open, it will not prevent the free penetration of shrinking liquid to and through all surface portions of the textile fabric.

Among the influences tending to keep the textile fabric in light engagement with the belt conveyor are the pull in the textile fabricwhich may be kept very low because the textile fabric is pulled forwards by the belt conveyor over the major part of its traveland the bouyancy of the textile fabric as a consequence of the air carried along by the textile fabric when it dives into the shrinking bath. The optimum utilization of both of these factors may be obtained, according to the invention, by conducting the process in such a manner that the textile fabric is guided by means of the belt conveyor in a path of movement extending downwards at an inclination in the major part of. the length of the shrinking bath so that, while the textile fabric is travelling alone with the belt conveyor, the latter will continuously tend to press the textile fabric further downwards in the bath against the influence of the forces tending to keep it afloat.

With particular advantage, according to the invention, the textile fabric may be supplied to the upper side of the return run of the belt conveyor adjacent the reversing position thereof, thereby to be fed into the shrinking bath together with the belt conveyor whereby a uniform and controlled immersion of the textile fabric into the shrinking bath is obtained.

Moreover, according to the invention, the textile fabric may be exposed, in the first part of its path of movement along the underside of the belt conveyor, to ultrasonic waves emitted directly towards the surface of the fabric. Thereby the most efficient utilization of the ultrasonic waves is obtained exactly in the Zone where the shrinking effect is to be intitiated as quickly and as strongly as possible, and at the same time the ultrasonic waves, when applied in this manner, will contribute towards pressing the textilefabric upwards so as to engage the underside of the belt conveyor at a light pressure.

A further contribution towards keeping the textile fabric in light engagement with the belt conveyor may be obtained, according to the invention, by producing a circulation of shrinking liquid in the shrinking bath from an inlet zone below the belt conveyor to an outlet zone above the belt conveyor and back through an external circulation system with a circulation pump. In this manner, the circulation of the shrinking liquid serves an additional purpose besides promoting the washing of all surface portions of the textile fabric with the shrinking liquid and ensuring the uniform concentration of the shrinking liquid throughout the bath, which is necessary in order to obtain uniform results of treatment.

After having left the shrinking bath, the textile fabric may, according to the invention, advantageously be carried further forwards on the upper side of a second perforated belt conveyor, and while being so conveyed being washed with washing liquid, which is supplied from above and discharged under the belt conveyor. In this manner, a considerably more efficient washing of the textile fabric may be obtained than by pulling the textile fabric through one or more washing or rinsing baths.

Moreover, it becomes possible in a simple manner to improve the washing by subdividing it into a plurality of stages. Thus, according to the invention, the textile fabric, While travelling on top of the second belt conveyor, may be washed with washing liquid of varying composition and/or temperature, viz, in such a manner that the washing liquid, which is supplied in the first zone of travel is hottest and preferably contains a neutralizing or penetrating agent, while the washing liquid supplied in the last zone of travel is coldest and preferably consists of pure water.

In carrying out this multistage washing, the washing liquid which is discharged under a zone of the path of movement of the fabric on top of the second belt conveyor may advantageously be used, according to the inventionupon heating and admixture of a neutralizing or penetrating agent, if desired-as washing liquid in a preceding zone of the path of movement. In this manner, the washing is carried out in counter current to the travel of the textile fabric whereby a good economy is obtained.

The invention also relates to an apparatus for carrying out the process described. According to the invention, the apparatus comprises a vessel for receiving shrinking liquid, a perforated belt conveyor mounted in said vessel, said belt conveyor running across guiding rollers adjacent the ends of said vessel, feeding means for supplying a continuous length of textile fabric to one end of said vessel, withdrawing means for withdrawing the textile fabric from the other end of said vessel, and means for driving said feeding means, said withdrawing means and said belt conveyor at speeds adjusted relative to one another in such a manner that a continuous length of textile fabric may thereby be caused to travel in a practically tension-free state in a path from said feeding means substantially along the underside of the lower run of said belt conveyor and then to said withdrawing means.

The invention will now be explained in further detail with reference to the accompanying drawings in which FIG. 1 diagrammatically shows a longitudinal section through one end of an apparatus constructed in accordance with one embodiment of the invention,

FIG. 2 a corresponding section through the other end of the apparatus,

FIG. 3 a section of the bottom of the vessel forming part of the apparatus illustrated, and

FIGS. 4 and 5 plan views of the parts of the apparatus illustrated in FIGS. 1 and 2 respectively, the textile material to be treated being omitted in these figures.

In the drawing, 1 is a vessel containing a shrinkage liquid, such as a phenol solution of a concentration of 3-8% up to a prescribed level 2. In the vessel 1 there is mounted a perforated belt conveyor 3, which runs across a roller 4 at the feeding end of the vessel and a roller 5 at the exit end of the vessel. The roller 4 is partly submerged under the liquid level 2. The roller 5 is arranged at a lower level than the roller 4, so that the lower run of the belt conveyor extends downwards at an inclination in the direction of movement of the belt conveyor, which is marked by an arrow, while the upper run 7 extends at an inclination upwards through the liquid and extends above the liquid level 2 in the zone immediately adjacent the roller 4. The belt conveyor 6 may e.g. consists of a wire netting of a relatively open structure.

Adjacent the feeding end of the vessel 1, a perforated supply tube 8 for shrinking liquid is arranged approximately at the bottom of the vessel, and adjacent the exit end of the vessel a perforated discharge tube 9 for shrinking liquid is arranged immediately below the water level 2, said-tubes 8 and 9 extending in substantially the whole width of the vessel 1. From the tube 9, an external circulation system 40 comprising a circulation pump 41 leads to the tube 8, so that a continuous circulation of the liquid in the vessel 1 is produced from the feeding end towards the exit end in a direction obliquely upwards through the lower run 6 of the belt conveyor. The circulation system may comprise a filter 42 for taking up impurities, particularly such as float on the liquid surface and are sucked with the liquid into the discharge tube 9. Moreover, a dosage apparatus 43 for shrinking liquid may be connected to the circulation system and this may be controlled by a liquid level feeler in the vessel 1 so as to continuously keep the liquid in the vessel 1 at the prescribed level. In this manner, the shrinking liquid supplied by the dosage apparatus 43 is mixed into the circulating shrinking liquid before entering into the vessel 1. Thereby it becomes possible to"ma'in'tain a uniform concentration throughout the shrinking bath. The circulation system may further comprise heating means 44 serving to keep the shrinking liquid at a predetermined temperature, e.g., about 60 C.

At the feeding end of the vessel 1 there is mounted a feeding mechanism which in the embodiment illustrated consists of an idle guiding roller 69, a driven smoothing roller 10, a driven pair of feeding rollers 11 and a driven depositing roller 12, the latter being located above the portion of theupper run 7 of the belt conveyor 3 present above the liquid level 2. The smoothing roller 10 is constructed in known manner with a right hand screw thread over one half thereof and a left hand screw thread over theother half thereof, so that the conveying action of the said screw threads on a textile fabric will tend to stretch the fabric in the transverse direction and to straighten out any marginal-folds. The pair of feeding rollers 11 are pressed-against one another at a pressure such as to be be smooth or be constructed with a plurality of blades by means of which it deposits the textile fabric on the upper run 7 of the belt conveyor 3 immediately adjacent the roller 4. The belt conveyor 3 is driven at a linear speed of movement which is somewhat less than the peripheral speed of the pair of rollers 11, such as will be explained in further detail below. 13 is a supply roller from which a textile fabric 14 is pulled off by means of the pair of feeding rollers 11 across guiding rollers 15 and 16 as well as the guiding rollers 69 and the smoothing roller previously mentioned. Instead of a single smoothing roller 10, two or more smoothing rollers may be used, and in that case it is preferable also to use a plurality of pairs of feeding rollers in order to keep the pulling force acting on the fabric at an advantageously low value. At the exit end of the vessel, a driven withdrawing roller 17 is mounted.

After having been deposited on the upper run of the belt conveyor 3 by means of the depositing roller 12, the textile fabric travels along with the belt conveyor around the roller 4 and then along the lower run 6 of the belt conveyor and around the roller 5 from which it continues upwards in a steep path to and around the withdrawing roller 17.

The peripheral speeds of the pair of feeding rollers 11, the depositing roller 12, and the withdrawing roller 17 and the speed of travel of the belt conveyor, are to be adjusted very accurately relative to one another depending on the degree of shrinking of the textile fabric. This adjustment may e.g. take place by means of well-known continuously variable transmissions and/ or separate variable speed motors. An example of driving means permitting of the required adjustments, is diagrammatically illustrated in FIG. 4. 45 is a variable speed electric motor which through a step-down gearing 46 and a chain drive 47 drives the roller 4 of the belt conveyor 3. Moreover, the motor 45 drives the depositing roller 12 by way of a so-called variator 48, i.e., a continuously variable transmission, and one of the driving rollers 11 is likewise driven through the variator 48 by way of a chain drive 49. A second variable speed electric motor 51 drives the withdrawing roller through a step-down gearing 52. Thus, by controlling the speeds of the two motors 45 and 51 and the transmission ratio of the variator 48, the relative speeds of rotation of the roller 4, the rollers 12 and 11 and the roller 17 may be adjusted. The smoothing roller 10 need not be synchronized with the other rollers and may therefore be driven by an independent electric motor 53. The peripheral speed of the roller 17 is to be equal to the peripheral speed of the pair of feeding rollers 11 multiplied by the shrinkage factor, i.e., the proportion of shrunk and nonshrunk length of the fabric, and the linear speed of the belt conveyor 3 is to be approximately the same as but preferably somewhat less than the peripheral speed of the roller 17. Besides being mutually adjusted, the said speeds should be adjusted in an absolute sense so as to obtain the desired time of treatment, or in other words the desired time of travel of the textile material through the bath. This time will depend on the nature of the textile material to be treated and the nature and concentration of the shrinking bath and should preferably be within the range of 412 seconds. The mutual adjustment of the speeds is performed in such a manner that the textile fabric in a substantially tensionfree state lightly engages the underside of the lower run 6 of the belt conveyor 3 in the major part of the length thereof. As previously explained, the buoyancy of the textile fabric under the influence of air carried along with same, and the liquid circulation in the shrinking bath, contribute towards establishing the said light engagement. In practice, however, the textile fabric may depend somewhat from the belt conveyor at the feeding thereof, seeing that in this zone the textile fabric has not yet been substantially shrunk and therefore has a higher linear speed than the belt conveyor.

In the bottom of the vessel 1, a battery of ultrasonic transducers is arranged, the emitting surfaces 18 of which are directed towards the lower run 6 of the belt conveyor and thereby towards the zone of the textile fabric where the shrinkage treatment is initiated.

In the embodiment illustrated a total of 12 ultrasonic transducers of the pulsed type are arranged according to the pattern illustrated in FIG. 3. An example of the operating figures of these ultrasonic transducers is as follow:

Area of emitting surface per transducer: 314 cm. thus in total 3768 cm.

Average power emitted per cm. of emitting surface: 12

watt, thus in total 54,216 kw.

Operating frequency: 25.5 kilocycles/sec.

Duration of each pulse: 0.025 sec.

Number of pulses per sec: 7.3.

From the emitting surfaces the ultrasonic waves emitted will travel predominantly in a direction perpendicular to the emitting surface while the intensity of the emission in other directions will decrease with the angle of departure from the perpendicular direction. Thus, the major portion of the power emitted will be present within an emitting cone having its apex approximately in the emitting surface. As an example, the emitting cone within which the intensity is above 90% of maximum, may have an apex angle of 57 (or for of maximum the apex angle may be With the arrangement of the ultrasonic transducers illustrated in FIG. 3 it will be realized that the emitting cones of the various ultrasonic transducers will overlap already at a relatively small distance above the emitting surface, and, consequently, at the level of the lower run 6 of the belt conveyor the emitting cones of adjacent transducers will overlap.

The use of pulsed or intermittent ultrasonic waves has the great advantage that a much higher peak value may be used than in the case of continuous waves Without damaging the fabric.

In continuation of the vessel 1, there is mounted a vessel 19 which by means of vertical partitions 20 and 21 is subdivided into three collecting tanks 22, 23, 24. A perforated belt conveyor 25 extends above the said collecting tanks, said belt conveyor running across rollers 26 and 27 and having a circulating direction opposite to that of the belt conveyor 3. From the withdrawing roller 17, the textile fabric continues its travel across a guiding roller 28 to the upper run of the belt conveyor 25 at the output end of which there is mounted a withdrawing mechanism comprising various guiding rollers and a pair of wringing rollers 29, which are driven from a variable speed electric motor 54 at a speed controlled by means of a tensionfeeling roller 30. The belt conveyor 25 is driven from the electric motor 51 through a chain drive 50 and a variator 55 at a speed which is so adjusted relative to the speed of the withdrawing roller 17, e.g., by means of a tensionfeeling roller-for which purpose the roller 28 may be used-that the fabric supported on the belt conveyor is not subjected to tensile stresses.

A plurality of overflow troughs 31-35 are arranged above the upper run of the belt conveyor 25 and extend in the transverse direction of the apparatus. Each overflow trough may be made from sheet metal bent to the shape illustrated in FIG. 2, and closed by end plates at both ends, to form an open channel with inclined outer side walls along which liquid supplied to the trough may overflow. The overflow trough 31 is provided with a perforated supply pipe 56 at the bottom thereof, which supply pipe is connected to a cold water supply line 57. Similar supply pipes are arranged at the bottom of the troughs 32-35. The overflow troughs 32 and 33 are connected with the collecting tank 22 by means of a circulation system 58, and the overflow troughs 34 and 35 are connected with the collecting tank 23 through another circulation system 59. The collecting tank 24 is connected with a waste pipe line 60. Liquid overflowing the side walls of the overflow troughs 31 to 35 flows through the textile fabric supported on the belt conveyor 25, thereby washing said textile fabric, and is collected in the collecting tanks present under the belt conveyor. Thus, in the last zone of its path of movement, the textile fabric is washed with cold water from the overflow trough 31. This water is then collected in the tank 22 and is pumped from the latter by means of a pump 61 into the overflow troughs 32 and 33 preferably through a heater 62 which raises the temperature of the washing water. In the zone under the overflow troughs 32 and 33, the textile fabric will then be washed with water of higher temperature, and this is collected in the tank 23 from which it is again pumped by means of a pump 63 into the overflow troughs 34 and 35 while preferably at the same time being further heated in a heater 64 and having a penetration or neutralizing agent added thereto by means of a dosage apparatus 65, so that in the first zone of its travel :along the upper side of the belt conveyor 35, the textile fabric is washed with hot water containing a penetration or neutralizing agent. Thereby, the shrinking action on the textile fabric is quickly and efiiciently interrupted, and in the two subsequent washing stages all residues of shrinking agents are removed and the textile fabric is cooled down to a temperature at which it is no longer plastic.

36 is a cord which extends through the apparatus in the same path as that provided for the textile fabric, and then back in a path above the bath across a plurality of guiding rollers 37. Such a cord may be provided at either side of the apparatus. They serve to facilitate the starting up of a new length of textile fabric, the corners of the frontmost end of the length of textile fabric being temporarily connected with the two cords, this connection being again interrupted when the textile fabric has been pulled through the pair of wringing rollers 29.

It has been found that by using the apparatus described, a very uniform treatment of a continuous length of textile fabric may be obtained so that no inner tensions or warping will occur and the tendency towards rolling up of the marginal portions of the textile fabric is kept at a minimum so that the waste caused by clean-cutting of the edges is likewise reduced to a minimum.

I claim:

1. A process for treating a continuous length of synthetic textile fabric for the purpose of making the material softer, less glossy and more voluminous, in which process the textile fabric is subjected to treatment in a strongly attacking shrinking bath, while at the same time being subjected to ultrasonic waves, and is immediately thereafter washed with a washing liquid that may contain a neutralizing agent for the shrinking liquid, characterized in that the textile fabric is passed through the shrinking bath in a path of movement extending under a perforated belt conveyor immersed in the bath, the speeds of supply and removal of the textile fabric to and from the shrinking bath and the speed of movement of the belt conveyor being so mutually adjusted that practically no tensile stresses occur in the textile fabric, and the latter is caused to follow a path of movement extending substantially along the underside of the belt conveyor.

2. A process as in claim 1, characterized in that the textile fabric is guided by means of the belt conveyor in a path of movement extending downwards at an inclination in the major part of the length of the shrinking bath.

3. A process as in claim 1 or 2, characterized in that the textile fabric is supplied to the upper side of the return run of the belt conveyor adjacent the reversing position thereof and is fed into the shrinking bath together with the belt conveyor.

4. A process as in any of the beforegoing claims, characterized in that the textile fabric is exposed in the first part of its path of movement along the underside of the belt conveyor to ultrasonic waves emitted directly towards the surface of the fabric.

5. A process as in any of the beforegoing claims, characterized in that a circulation of shrinking liquid is produced in the shrinking bath from an inlet zone below the belt conveyor to an outlet zone above the belt conveyor (and back through an external circulation system with circulation pump.

6. A process as in any of the beforegoing claims, characterized in that the textile fabric, after having left the shrinking bath, is carried further forwards on the upper side of a second perforated conveyor and, while being so conveyed, is washed with washing liquid which is supplied from above and discharged under the belt conveyor.

7. A process :as in claim 6, characterized in that the textile fabric, while travelling on top of the second belt conveyor, is Washed with washing liquid of varying composition and/or temperature, viz in such a manner that the washing liquid which is supplied in the first zone of travel is hottest, and preferably contains a neutralizing or penetrating agent, while the washing liquid supplied in the last zone of travel is coldest and preferably consists of pure water.

8. A process as in claim 7, characterized in that the washing liquid which is discharged under a zone of the path of movement of the fabric on top of the second belt conveyor is used, upon heating and admixture of a neutralizing or penetrating agent, if desired, as washing liquid in a preceding zone of the path of movement.

No references cited.

NORMAN G. TORCHIN, Primary Examiner.

J. P. BRAMMER, Assistant Examiner. 

1. A PROCESS FOR TREATING A CONTINUOUS LENGTH OF SYNTHETIC TEXTILE FABRIC FOR THE PURPOSE OF MAKING THE MATERIAL SOFTER, LESS GLOSSY AND MORE VOLUMINOUS, IN WHICH PROCESS THE TEXTILE FABRIC IS SUBJECTED TO TREATMENT IN A STRONGLY ATTACKING SHRINKING BATH, WHILE AT THE SAME TIME BEING SUBJECTED TO ULTRASONIC WAVES, AND IS IMMEDIATELY THEREAFTER WASHED WITH A WASHING LIQUID THAT MAY CONTAIN A NEUTRALIZING AGENT FOR THE SHRINKING LIQUID, CHARACTERIZED IN THAT THE TEXTILE FABRIC IS PASSED THROUGH THE SHRINKING BATH IN A PATH OF MOVEMENT EXTENDING UNDER A PERFORATED BELT CONVEYOR IMMERSED IN THE BATH, THE SPEEDS OF SUPPLY AND REMOVAL OF THE TEXTILE FABRIC TO AND FROM THE SHRINKING BATH AND THE SPEED OF MOVEMENT OF THE BELT CONVEYOR BEING SO MUTUALLY ADJUSTED THAT RACTICALLY NO TENSILE STRSSES OCCUR IN THE TEXTILE FABRIC, AND THE LATTER IS CAUSED TO FOLLOW A PATH OF MOVEMENT EXTENDING SUBSTANTIALLY ALONG THE UNDERSIDE OF THE BELT CONVEYOR. 